🦴 Location of Major Bones
Axial Skeleton
- Cranium — protects the brain
- Vertebrae — 33 bones forming the spinal column
- Ribs (12 pairs) — protect heart & lungs
- Sternum — breastbone, anterior rib attachment
Shoulder Girdle
- Clavicle — collarbone, links sternum to scapula
- Scapula — shoulder blade, site of shoulder joint
KEY: Axial = skull, spine, ribs, sternum. Appendicular = limbs + girdles.
🦴 Bones of the Limbs
Upper Limb
- Humerus — upper arm
- Radius & Ulna — forearm (radius = thumb side)
- Carpals — 8 wrist bones
- Metacarpals — palm (5 bones)
- Phalanges — finger bones
Lower Limb
- Pelvis — hip bone, connects spine to legs
- Femur — thigh bone (longest bone)
- Patella — kneecap
- Tibia & Fibula — lower leg
- Tarsals, Metatarsals, Phalanges — foot & toes
⚙️ Functions of the Skeleton
- Support — framework maintaining upright posture
- Posture — keeps body in correct alignment
- Protection — cranium protects brain; ribs protect heart/lungs
- Movement — bones act as levers for muscle action
- Blood cell production — red & white cells made in red bone marrow
- Mineral storage — calcium & phosphorus stored in bone matrix
EXAM TIP: Give a sporting example for each function — e.g. vertebrae support a weightlifter's spine.
🔗 Types of Synovial Joint
Hinge Joints (flexion/extension only)
- Knee — femur + tibia
- Elbow — humerus + radius + ulna
Ball & Socket Joints (greatest range)
- Shoulder — humerus + scapula
- Hip — femur + pelvis
Other Synovial Joint Components
- Ligament — bone to bone; stabilises joint
- Cartilage — smooth covering; reduces friction
- Tendon — muscle to bone; transmits force
🔄 Types of Movement
At Hinge Joints
- Flexion — decreasing angle at joint (e.g. bending knee)
- Extension — increasing angle at joint (e.g. straightening knee)
At Ball & Socket Joints
- Flexion / Extension — forward/backward movement
- Abduction — moving limb away from midline
- Adduction — moving limb towards midline
- Rotation — turning around long axis
- Circumduction — circular movement combining all of above
Apply to sport: a gymnast performing a cartwheel uses shoulder circumduction.